Removed assertion that wait failing due to expected behavior

syncInitialization was failing assertion because all bytes were read, but test was before additional bytes were read into buffer

core/src/main/java/com/riiablo/mpq_bytebuf/MpqBufferStream.java

@@ -146,7 +146,6 @@ public final class MpqBufferStream extends InputStream {
   Promise syncInitialization() {
     if (init == null) throw new IllegalStateException("not initialized via MpqBufferStream#initialize()");
     init.syncUninterruptibly();
-    assert buffer.isReadable();
     return init;
   }